Gillard won't employ the most commonly used phrase to describe her plan - 'carbon tax' - preferring to dub it a carbon 'price' (a Google search for carbon tax pulls up more than 10 million hits, while carbon price draws little more than 1 million).

Abbott, on the other hand, must think 'carbon tax' sounds much less palatable to the public. He hammered the words in his speech, repeating them 12 times. The word 'tax' he used more than any other, a total of 16 times.

Gillard also mentioned the word 'tax' - but only three times and always followed by the magic word: 'cut'.

And the Prime Minister kept repeating the word 'pollution' - she said it eight times, while Abbott decided to go with the term 'emissions', repeating it five times and not mentioning 'pollution' once.

How many times Prime Minister Julia Gillard used the following words:

Carbon price: 6

Carbon tax: 0

Tax cut: 3

Pollution: 8

Emissions: 0

How many times Opposition Leader Tony Abbott used the following words: